The Tongcheng School (Tongchengpai 桐城派) was a group of theoreticians of literature active during the early and high Qing period 清 (1644-1911). It was founded by Fang Bao 方苞 (1668-1749), and the most prominent representatives were Liu Dakui 劉大櫆 (1698-1779) and Yao Nai 姚鼐 (1732-1815). These three people are called the "three ancestors" of the School (Tongcheng sanzu 桐城三祖). Some authors count Yao Nao’s uncle Yao Fan 姚範 (1702-1771) to the founders of the School, while others speak of the "four ancestors" (sizu 四祖) Dai Shiming 戴名世 (1653-1713), Fang, Liu, and Yao. Most of the adherents hailed from the city of Tongcheng in Anhui. Gui Youguang 歸有光 (1506-1571) can be seen as a forerunner of the School.
The main proposition of the school was the concept of "standards of righteousness" (yifa 義法), a word first mentioned in the preface to the chronological tables in the history book Shiji 史記, where it is said that Confucius, while compiling the Spring and Autumn Annals (Chunqiu 春秋), he established the standards of righteousness in polishing the wording of the Annals and simultaneously judging over historical events. Fang Bao used the term to judge over literary quality, and explained (in his essay You shu Huozhi zhuan hou 又書貨殖傳後) that the word "righteousness" (yi 義) corresponded to a statement in the Classic Yijing 易經 "Book of Changes", where it is said that the superior man "orders his words according to [the truth of] things" (yan you wu 言有物; hexagram Jiaren 家人, transl. Legge), while the term "standard" (fa 法) meant that "the words are all orderly" (yan you xu 言有序; hexagram Gen 艮). "Righteousness" thus referred to the content, and "standards" to the form of texts which had to correspond to each other. The shape had to be adapted to the content of a text, and only then, an essay or letter would become "elegant and pure" (yajie 雅潔).
Liu Dakui developed the concept of "searching for the spirit of a texts with the help of sound" (yin sheng qiu qi 因聲求氣). A text was only capable to "clarify its arguments" (ming yili 明義理) and to "adapt to practical use" (shi shiyong 適世用) if the author had sufficient capability or talent (nengshi 能事) to write in a good rhythm and sound (yinjie 音節). The Way of writing (xing wen zhi dao 行文之道) was mainly based on spirit (shen wei zhu 神為主), supported by flow of energy (qi fu zhi 氣輔之). While words and sentences were the crude matter of a text, and rhythm and sound the grains, spirit and energy were its essence (see Lunwen ouji 論文偶記). The term yili 義理 must not only be understood in a logical sense, but also in a philosophical sense, namely the Neo-Confucian universal principle (li 理) as expressed in the moral attitude of righteousness. In this way, the activity of writing was embedded in a coherent universal and cosmological worldview.
Yao Nai expounded Liu’s theory and stressed that the search for excellent literature had to pass a stage of "crudeness" before coming into the age of matured fineness. The formal structure of texts as well as shape and sound were the "crude" aspect of literature (ge lü sheng se zhe, wen zhi cu ye 格律聲色者，文之粗也), while the refined aspect was found in "spirit, the principle, energy and taste" (shen li qi wei zhe, wen zhi jing ye 神理氣味者，文之精也). The four refined aspects could not go without the crude ones (see Guwen cilei zuan xu 古文辭類纂序). Yao discerned between two basic styles of texts, namely such with the "softness of Yin" (yin rou 陰柔), and such with the "hardness of Yang" (yang gang 陽剛), and criticized that most authors preferred a one-sided soft Yin style. Another point of critique towards contemporary writers was the lopsidedness in the emphasis of a text’s aim, to such an extent that authors only worked at one focus, namely argument (yili 義理), critical analysis and collation (kaoju 考據), or textual composition (cizhang 辭章). Yao insisted that a writer had to rely on all three aspects, and that scholarly sound articles and excellent literature could not miss one of these three aspects (see Shu'an wenchao xu 述庵文鈔序).
Essays written by representatives of the School are characterized as "elucidating the Way and supportive in teaching" (chan dao yi jiao 闡道翼教), achieved by the selection of simple and clear language and logical composition, the renunciation of rhymes and verses or paired language (pianju 駢句), and the attempt to strive for "pure authenticity and elegant trueness" (qingzhen yazheng 清真雅正). The most outstanding examples are Fang Bao's Yuzhong zaji 獄中雜記 and Zuo Zhongyigong yishi 左忠毅公逸事, and Yao Nai's Deng Taishan ji 登泰山記. The most widely circulating book was Yao’s anthology Gu wenci leizuan 古文辭類纂.
The influence of the Tongcheng School reached beyond the city of that name, and was felt until the end of imperial China. Apart from the four founders, the School includes the disciples of Fang Bao, namely Lei Hong 雷鋐 (1697-1760), Zhu Shixiu 朱仕琇 (1715-1780), Lu Hong 魯鴻 (1722-1789), Shen Tong 沈彤, Wang Youpu 王又樸 (1681-1760), Shen Tingfang 沈庭芳, Wang Zhaofu 王兆符 (1681-1723), Chen Dashou 陳大受 (d. 1751), Li Xueyu 李學裕 (1691-1745) and Lu Jiugao 魯九皋 (1732-1784), the disciples of Liu Dakui, namely Qian Bojiong 錢伯坰 (1738-1812), Wang Zhuo 王灼, Wu Ding 吳定, Cheng Jinfang 程晉芳 (1718-1784), Yun Jing 惲敬 (1757-1817), Zhang Huiyan 張惠言 (1761-1802) and Wu Dexuan 吳德旋 (1767-1840), and the disciples of Yao Nai, i.e. Guan Tong 管同 (1780-1831), Mei Zengliang 梅曾亮 (1786-1856), Fang Dongshu 方東樹 (1772-1851), Li Zhaoluo 李兆洛 (1769-1841), Yao Chun 姚椿 (1777-1852), and Yao Ying 姚瑩 (1785-1853).
Other representatives are Zhu Qi 朱琦, Long Qirui 龍啟瑞 (1814-1858), Chen Xueshou 陳學受, Wu Jiabin 吳嘉賓 (1803-1864), Deng Xianhe 鄧顯鶴 (1777-1851), Sun Dingcheng 孫鼎臣 (1819-1859), Lu Yitong 魯一同 (1805-1863) and Shao Yichen 邵懿辰 (1810-1861).
In the late 19th century, Zeng Guofan 曾國藩 (1811-1872) praised the Tongcheng School, but he and his disciples Zhang Yuzhao 張裕釗 (1823-1894), Wu Rulun 吳汝綸 (1840-1903), Ma Qichang 馬其昶 (1855-1930), Yao Yongpu 姚永樸 (1860-1937), Yao Yonggai 姚永概 (1866-1923), and Wu Kaisheng 吳闓生 (1879-1951) transformed it to the so-called Hunan School (Xiangxiangpai 湘鄉派).